The fieldset element represents a set of form controls optionally grouped under a common name.

The name of the group is given by the first legend element that is a child of the fieldset element, if any. The remainder of the descendants form the group.

The disabled attribute, when specified, causes all the form control descendants of the fieldset element, excluding those that are descendants of the fieldset element's first legend element child, if any, to be disabled.

The form attribute is used to explicitly associate the fieldset element with its form owner. The name attribute represents the element's name.

The disabled IDL attribute must reflect the content attribute of the same name.

The following snippet shows a fieldset with a checkbox in the legend that controls whether or not the fieldset is enabled. The contents of the fieldset consist of two required text fields and an optional year/month control.

In this example, if the outer "Use Club Card" checkbox is not checked, everything inside the outer fieldset, including the two radio buttons in the legends of the two nested fieldsets, will be disabled. However, if the checkbox is checked, then the radio buttons will both be enabled and will let you select which of the two inner fieldsets is to be enabled.